This isn't the Spinal Tap you remember

Yes, the trio are going "Unwigged and Unplugged," as their tour title states, with acoustic guitars and stools. This will also enable the actors to play songs from their folk music mockumentary "The Mighty Wind."

The 65-year-old actor, who is also known to do voices such as Mr. Burns and Ned Flanders on Fox's sturdy animated classic "The Simpsons," said they already had done two tours as the fictional (but now kind of real) metal act Spinal Tap.

"We aren't big fans of repeating ourselves," Shearer said. So far, he said, the audiences "have been wonderful. Houston was ridiculous with the energy."

He's amazed that the legacy of the 1984 movie resonates to this day, with TV shows such as "Extras" and "The Office" using visual techniques from the film.

"It's a movie nobody wanted to make," Shearer said. "Yet the movie has outlived the careers of the people who didn't want to make the movie. There are kids discovering it all the time. We've had musicians say they've learned what not to do by watching the movie. It's become an educational film!"

The film was also prescient when Shearer's character Derek got caught at airport security with foil-wrapped produce in his trousers. Shearer recalls a case earlier this decade in which an NBA player was caught with foil-wrapped marijuana in his pants.

"I guess," Shearer said, "he didn't see the movie."

Shearer's biggest payday hasn't been "Spinal Tap." ("It's been more emotionally than financially rewarding," he said.) It's been "The Simpsons," which will become the longest-running prime-time entertainment series in U.S. history next year. Trade publications say he and the other top voice talent get a whopping $400,000 per episode.

"I cherish the advice a fairly well-known comedy friend of mine Eric Idle [of 'Monty Python' fame] gave me," Shearer said. "The key is to take as much of Rupert Murdoch's money as possible!"